SQL SERVER – Puzzle – SELECT * vs SELECT COUNT(*)

Posted by pinaldave on SQL Authority See other posts from SQL Authority or by pinaldave
Published on Mon, 30 May 2011 01:30:27 +0000 Indexed on 2011/06/20 16:29 UTC
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Earlier this weekend I have presented at Bangalore User Group on the subject of SQL Server Tips and Tricks. During the presentation I have asked a question to attendees. It was very interesting to see that I have received various different answer to my question. Here is the same question for you and I would like to see what your answer to this question.

Question: SELECT * gives error when executed alone but SELECT COUNT(*) does not. Why?

Select * - resulting Error

Select * - resulting Error

Select count * - NOT resulting Error

Select count * - NOT resulting Error

Please leave your answer as comment over here. If you prefer you can blog post about this on your blog and put a link here. I will publish valid answer with due credit in future blog posts.

Reference: Pinal Dave (http://blog.SQLAuthority.com)

Filed under: PostADay, Readers Question, SQL, SQL Authority, SQL Puzzle, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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